Note: I sold my NES a long time ago, so I am going entirely from memory here.
One of the games I played a lot back in the day was Defender of the Crown. I will be critiquing it here, but I genuinely enjoyed the game. I never played any of the PC ports, which were apparently technically superior to the NES version.
Here is the primary problem: Multiple game modes. In the 8-bit era, this was almost always a handicap because there is only so much room on a cartridge. Games that did one thing could do it well, but games with multiple game modes did not do as well because the limited resources were split between multiple different games. In DOTC, you had a tournament game with jousting and one-on-one combat, a mini-game that allowed you to raid a castle, laying siege to a castle, defending your castle from a siege, and an army-vs-army strategy game. Six games in one, and none of them were pulled off all that well.
I never did very well. I would build my army and eventually get crushed by invading Norman armies from the south. Sometimes I would be defeated by my fellow Saxons before the Normans even got to me. So I played dozens of games, and never was close to winning the game… until one particular day.
Basically, I got lucky. The Saxons and Normans were fighting each other and I was at the northern part of the map quietly building my army. Nobody bothered me, so I did not have to spend resources defending my castle or my lands. I slowly gained territory and then became powerful enough to go on the offensive. I rampaged across England, taking down the other kingdoms until only one Norman was left to oppose me. I took his castle and that was that. It was entirely luck, nothing more. I did not win on skill, and I was never able to replicate that win.
It was a deeply flawed game, but it was fun.